1. Field of the Invention
The present invention relates generally to the field of graphical programming languages, and more particularly, to an icon in a graphical programming language that will communicate with many different instruments.
2. Related Art
In textual languages such as C, PASCAL, or BASIC, one programs using keywords following rules of syntax. In a graphical language, one connects icons together using a mouse to generate a program resembling a data flow diagram. Hewlett Packard Visual Engineering Environment (HP VEE) for Windows is a graphical programming language designed for test and measurement applications.
In HP VEE, one programs by selecting objects (icons) from menus, placing those objects within a working area environment, and connecting them together using a mouse. The lines connecting the objects carry data or control signals.
HP VEE provides two easy ways to control instruments: instrument drivers and the Direct I/O object. Instrument drivers are user interfaces that control an instrument from a computer screen. With a driver one does not need to know the unique software commands that control a particular instrument. Once the instrument has been set up using menu selections and dialog boxes, the driver will automatically send the right command strings over the bus.
With the Direct I/O object, one has to know the instrument command strings. HP VEE provides a convenient method of transmitting commands and receiving data. Using Direct I/O one can communicate with any instrument that connects to one of the supported interfaces, such as GPIB, RS-232, or VXI interfaces.
Although instrument drivers provide maximum ease-of-use and save development time, they are not always available. With the Direct I/O one can communicate with any instrument from any vendor over standard interfaces. Although it requires slightly more effort than an instrument driver, the Direct I/O yields faster execution speeds.
HP VEE's current Direct I/O object is configured for only one device. Controlling several instruments at a time means having to use several Direct I/O objects.